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On Having a Laugh – by Gerlich and Tscheuschner (2009)

Posted in Commentary on March 14, 2010| 60 Comments »

There’s a paper out which has created some excitement, On Falsification Of The Atmospheric CO2 Greenhouse Effects, by Gerlich & Tscheuschner (2009). It was published in International Journal of Modern Physics B. I don’t know what the B stands for.

Usually I would try and read a paper all the way through to understand it, then reread it.. but I got as far as page 55 out of 115 – even the seminal Climate Modeling through Radiative Convective Methods by Ramanathan & Coakley (1978) paper only had 25 pages.

Quite a few points have already jumped out at me that made me not want to read the whole thing:

First, a lot of time was spent showing that greenhouses and bodies surrounded by glass (or anything that stops air movement) retain heat not because of absorption and reradiation of longwave energy but because convection is reduced.

Why spend so long on it when everyone agrees. Sadly the “so-called greenhouse effect” became that because it passed into common language to describe this effect even though it’s not the right description.

Even in CO2 – An Insignificant Trace Gas? Part Six – Visualization I said:

I tried to think of a good analogy, something to bring it to life..

But didn’t mention greenhouses, because the greenhouse isn’t a good analogy..

This is a concern if it’s a serious paper, because attacking arguments that no one agrees with is the strawman fallacy, a refuge of people with no strong argument.

Here is a nice example, commenting on a paper by Lee, who says that the “greenhouse” term is a misnomer:

Lee continues his analysis with a calculation based on radiative balance equations, which are physically questionable.. Nevertheless, Lee’s paper is a milestone marking the day after which every serious scientist or science educator is no longer allowed to compare the greenhouse with the atmosphere, even in the classroom, which Lee explicitly refers to.

The authors of this paper don’t actually explain where Lee’s equations are questionable, instead draw attention to a day that should be marked down in history.. and use that to show that anyone mentioning “greenhouses” have got it wrong.

None of the papers that discuss the radiative-convective method actually argue from the greenhouse. So why are the authors of this paper spending so much time on it?

Second, attacking poor presentations with a mixture of correct (but really irrelevant) and incorrect arguments.

They cite, not a paper, but an Encyclopedia..

In the 1974 edition of Meyer’s Enzyklopadischem Lexikon one finds under “glass house eff ect”:

Name for the influence of the Earth’s atmosphere on the radiation and heat budget of the Earth, which compares to the e ffect of a glass house: Water vapor and carbon dioxide in the atmosphere let short wave solar radiation go through down to the Earth’s surface with a relative weak attenuation and, however, reflect the portion of long wave (heat) radiation which is emitted from the Earth’s surface
(atmospheric backradiation).

Disproof: Firstly, the main part of the solar radiation lies outside the visible light. Secondly, reflection is confused with emission.

Nice. They have brought this up a few times. Yes, technically we call infrared that part of the radiation that is longer wavelength than visible light. So anything >700nm is infrared. Any yet, in common terminology, often cited to a point of pain, we use “longwave” to mean that radiation over 4μm because 99% of it is radiated from the earth, and we use “shortwave” to mean that radiation under 4μm which is solar radiation.

So their first “disproof” isn’t a disproof. And their second one is simply picking a terminology mistake in an encyclopedia. Yes, the encyclopedia has mixed up the phenomenon.

Why are they citing from this source?

Third, another example of “destroying” the opponent’s argument..

They quote another source:

The infrared radiation that is emitted downwards from the atmosphere (the so-called back-radiation) raises the energy supply of the Earth’s surface.

And comment:

The assumption that if gases emit heat radiation, then they will emit it only downwards, is rather obscure.

It wasn’t what their source actually said. Their source didn’t say, or imply, that radiation was emitted only downward.

Fourth, and most importantly, the paper gives the appearance of discussing prior work by discussing a real mix of very old work and lots of more recent comments by people in their “introduction” to something quite different. That is they are citing from papers which are introducing another subject while not attempting to demonstrate any formal proof of the inappropriately named “greenhouse effect”. They don’t discuss the relevant modern work that attempts to prove the relevance and solution of the radiative transfer equations.

They do reference one key paper but never discuss it to point out any problems.

The paper in question is S. Manabe and R.F. Strickler, Thermal Equilibrium of the Atmosphere with Convective Adjustment, J. Atmosph. Sciences 21, 361-385 (1964)

It is referenced through this quote:

The influence of CO2 on the climate was also discussed thoroughly in a number of publications that appeared between 1909 and 1980, mainly in Germany. The most influential authors were Moller, who also wrote a textbook on meteorology, and Manabe (the citation). It seems, that the joint work of Moller and Manabe has had a signifi cant influence on the formulation of the modern atmospheric CO2 greenhouse conjectures and hypotheses, respectively.

The work that most recent papers on the solution to the radiative transfer equations discuss or cite is Ramanathan and Coakley (1978) – often along with a citation of M&S – and of course Ramanathan and Coakley cite and discuss Manabe and Strickler (1964). That is, anyone calculating the effect of CO2 and other trace gases on the surface temperatures.

Why not open up these two great papers and show the flaws? Ramanathan and Coakley are never even cited. Manabe and Strickler aren’t discussed.

R&C is 25 pages long and works through a lot of thermodynamics in their paper. If Gerlich & Tscheuschner want to get a result, show their flaws. It should be a breeze for them..

This doesn’t instill any confidence in the paper. I starting writing this post a few weeks ago and at the time wrote:

One day I may find the energy to read and reread all 115 pages and do them justice. Perhaps there is some revelation inside. More likely, they are having a laugh. Otherwise why is half the paper nothing to do with disproving the theory that modern atmospheric physicists believe?

I’m sure they would say otherwise.. And I’m certain we would get on great over a few drinks. If we drank enough I’m sure they would admit they did it for a bet..

Non-Conclusion

If Gerlich & Tscheuschner want to be taken seriously maybe they can write a paper which is 20-30 pages long – it should be enough – and they can ignore greenhouses and encyclopedia references and what people say in introductions to less relevant works.

Their paper could reference and discuss recent work which from first principles demonstrate and solve the radiative transfer equations. And they should show the flaw in these papers. Use Ramanathan and Coakley (1978) – everyone else references it.

On that paper: Climate Modeling through Radiative Convective Methods – R&C are into the maths by page 2 and don’t mention greenhouses. I would recommend this excellent paper (you should be able to find it online without paying) to anyone who wants to learn more about the approach to solving this difficult but well-understood problem. Even if you don’t want to follow their maths there is lots to learn.

Gerlich & Tscheuschner waste 50 pages with irrelevance and poorly directed criticism.. if they have produced a great insight it will be lost on many.

In New Theory Proves AGW Wrong! I commented that many ideas come along which are widely celebrated.

Some “disprove” the “greenhouse effect” or modify it to the extent that if their ideas are correct our ideas about the (inappropriately named) greenhouse effect are quite wrong.

Some disprove AGW (anthropogenic global warming). There is a world of difference between the two.

This paper falls into the first category. I also commented that the papers in the first category usually disprove each other as well, so it’s not “one more nail in the greenhouse effect” – it’s “one more nail in the last theory” and the theories that will inevitably follow.

Interestingly (for me), since I wrote that article: New Theory Proves AGW Wrong! someone produced a list of a few papers that I should “disprove”. One was this paper by Gerlich and Tschueschner, another was by Miskolczi. Yet they disprove each other and both disprove what this person promoted as their own theory.

This doesn’t prove anyone wrong – just they can’t all be right. One or zero..

And I’ll be the first to admit I haven’t proven Gerlich and Tschueschner wrong in their central theory. I have pointed out a few “areas for improvement” in their paper but these are all distractions from the main event. More interesting stuff to do.

Update – new post: On the Miseducation of the Uninformed by Gerlich and Tscheuschner (2009)

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Why Global Mean Surface Temperature Should be Relegated, Or Mostly Ignored

Posted in Commentary, Measurement on March 2, 2010| 49 Comments »

There’s a huge amount of attention paid to the air temperature 6ft off the ground all around the continents of the world. And there’s an army of bloggers busy re-analyzing the data.

It seems like one big accident of history. We had them, so we used them, then analyzed them, homogenized them, area-weighted them, re-analyzed them, wrote papers about them and in so doing gave them much more significance than they deserve. Consequently, many people are legitimately confused about whether the earth is warming up.

I didn’t say land surface temperatures should be abolished. Everyone’s fascinated by their local temperature. They should just be relegated to a place of less importance in climate science.

Problems with Air Surface Temperature over Land

If you’ve spent any time following debates about climate, then this one won’t be new. Questions over urban heat island, questions over “value-added” data, questions about which stations and why in each index. And in journal-land, some papers show no real UHI, others show real UHI..

One of the reasons I posted the UHI in Japan article was I hadn’t seen that paper discussed, and it’s interesting in so many ways.

The large number of stations (561) with high quality data revealed a very interesting point. Even though there was a clear correlation between population density and “urban heat island” effect, the correlation was quite low – only 0.44.

Lots of scatter around the trend:

Estimate of actual UHI by referencing the closest rural stations

Estimate of actual UHI by referencing the closest rural stations - again categorized by population density

This doesn’t mean the “trend” wasn’t significant, as the result had a 99% confidence around it. What it meant was there was a lot of variability in the results.

The reason for the high variability was explained as micro-climate effects. The very local landscape, including trees, bushes, roads, new buildings, new vegetation, changing local wind patterns..

Interestingly, the main effect of UHI is on night-time temperatures:

Temperature change per decade: time of day vs population density

Temperature change per decade: time of day vs population density

Take a look at the top left graphic (the others are just the regional breakdown in Japan). Category 6 is the highest population density and category 3 the lowest.

What is it showing?

If we look at the midday to mid-afternoon temperatures then the average temperature change per decade is lowest and almost identical in the big cities and the countryside.

If we look at the late at night to early morning temperatures then average change per decade is very dependent on the population density. Rural areas have experienced very little change. And big cities have experienced much larger changes.

Night time temperatures have gone up a lot in cities.

A quick “digression” into some basic physics..

Why is the Bottom of the Atmosphere Warmer than the Top while the Oceans are Colder at the Bottom?

The ocean surface temperature somewhere on the planet is around 25°C, while the bottom of the ocean is perhaps 2°C.

Ocean temperature vs depth, Grant Bigg, Oceans and Climate (2003)

Ocean temperature vs depth, Grant Bigg, Oceans and Climate (2003)

The atmosphere at the land interface somewhere on the planet is around 25°C, while the top of the troposphere is around -60°C. (Ok, the stratosphere above the troposphere increases in temperature but there’s almost no atmosphere there and so little heat).

Typical temperature profile in the troposphere

Typical temperature profile in the troposphere

The reason why it’s all upside down is to do with solar radiation.

Solar radiation, mostly between wavelengths of 100nm to 4μm, goes through most of the atmosphere as if it isn’t there (apart from O2-O3 absorption of ultraviolet). But the land and sea do absorb solar radiation and, therefore, heat up and radiate longwave energy back out.

See the CO2 series for a little more on this if you wonder why it’s longwave getting radiated out and not shortwave.

The top of the ocean absorbs the sun’s energy, heats up, expands, and floats.. but it was already at the top so nothing changes and that’s why the ocean is mostly “stratified” (although see Predictability? With a Pinch of Salt please.. for a little about the complexity of ocean currents in the global view)

The very bottom of the atmosphere gets warmed up by the ground and expands. So now it’s less dense. So it floats up. Convective turbulence.

This means the troposphere is well-mixed during the day. Everything is all stirred up nicely and so there are more predictable temperatures – less affected by micro-climate. But at night, what happens?

At night, the sun doesn’t shine, the ground cools down very rapidly, the lowest level in the atmosphere absorbs no heat from the ground and it cools down fastest. So it doesn’t expand, and doesn’t rise. Therefore, at night the atmosphere is more stratified. The convective turbulence stops.

But if it’s windy because of larger scale effects in the atmosphere there is more “stirring up”. Consequently, the night-time temperature measured 6ft off the ground is very dependent on the larger scale effects in the atmosphere – quite apart from any tarmac, roads, buildings, air-conditioners – or urban heat island effects (apart from tall buildings preventing local windy conditions)

There’s a very interesting paper by Roger Pielke Sr (reference below) which covers this and other temperature measurement subjects in an accessible summary. (The paper used to be available free from his website but I can’t find it there now).

One of the fascinating observations is the high dependency of measured night temperatures on height above the ground, and on wind speed.

Micro-climate and Macro-climate

Perhaps the micro-climate explains much of the problems of temperature measurement.

But let’s turn to a thought experiment. No research in the thought experiment.. let’s take the decent-sized land mass of Australia. Let’s say large scale wind effects are mostly from the north to south – so the southern part of Australia is warmed up by the hot deserts.

Now we have a change in weather patterns. More wind blows from the south to the north. So now the southern part of Australia is cooled down by Antarctica.

This change will have a significant “weather” impact. And in terms of land-based air surface temperature we will have a significant change which will impact on average surface temperatures (GMST). And yet the energy in the climate system hasn’t changed.

Of course, we expect that these things average themselves out. But do they? Maybe our assumption is incorrect. At best, someone had better start doing a major re-analysis of changing wind patterns vs local temperature measurements. (Someone probably did it already, as it’s a thought experiment, there’s the luxury of making stuff up).

How much Energy is Stored in the Atmosphere?

The atmosphere stores 1000x less energy than the oceans. The total heat capacity of the global atmosphere corresponds to that of only a 3.2 m layer of the ocean.

So if we want a good indicator – a global mean indicator – of climate change we should be measuring the energy stored in the oceans. This avoids all the problems of measuring the temperature in a highly, and inconsistently, mobile lightweight gaseous substance.

Right now the ocean heat content (OHC) is imperfectly measured. But it’s clearly a much more useful measure of how much the globe is warming up than the air temperature a few feet off the ground.

If the primary measure was OHC with the appropriately-sized error bars, then at least the focus would go into making that measurement more reliable. And no urban heat island effects to worry about.

How to Average

There’s another problem with the current “index” – averaging of temperatures, a mix of air over land and sea surface temperatures. There is a confusing recent paper by Essex (2007), see the reference below, just the journal title says it’s not for the faint-hearted, which says we can’t average global temperatures at all –  however, this is a different point of view.

There is an issue of averaging land and sea surface temperatures (two different substances). But even if we put that to one side there is still a big question about how to average (which I think is part of the point of the confusing Essex paper..)

Here’s a thought experiment.

Suppose the globe is divided into 7 equal sized sections, equatorial region, 2 sub-tropics, 2 mid-latitude regions, 2 polar regions. (Someone with a calculator and a sense of spherical geometry would know where the dividing lines are.. and we might need to change the descriptions appropriately).

Now suppose that in 1999 the average annual temperatures are as follows:

  • Equatorial region: 30°C
  • Sub-tropics: 22°C, 22°C
  • Mid-latitude regions: 12°C, 12°C
  • Polar regions: 0°C, 0°C

So the “global mean surface temperature” = 14°C

Now in 2009 the new numbers are:

  • Equatorial region: 26°C
  • Sub-tropics: 20°C, 20°C
  • Mid-latitude regions: 12°C, 12°C
  • Polar regions: 5°C, 5°C

So the “global mean surface temperature” = 14.3°C – an increase of 0.3°C. The earth has heated up 0.3°C in 10 years!

After all, that’s how you average, right? Well, that’s how we are averaging now.

But if we look at it from more a thermodynamics point of view we could ask – how much energy is the earth radiating out? And how has the radiation changed?

After all, if we aren’t going to look at total heat, then maybe the next best thing is to use how much energy the earth is radiating to get a better feel for the energy balance and how it has changed.

Energy is radiated proportional to σT4, where T is absolute temperature (K).  0°C = 273K. And σ is a well-known constant.

Let’s reconsider the values above and average the amount of energy radiated and find out if it has gone up or down. After all, if temperature has gone up by 0.3°C the energy radiated must have gone up as well.

What we will do now is compare the old and new values of effective energy radiated. (And rather than work out exactly what it means in W/m2, we just calculate the σT4 value for each region and sum).

  • 1999 value = 2714.78 (W/arbitrary area)
  • 2009 value = 2714.41 (W/arbitrary area – but the same units)

Interesting? The “average” temperature went up. The energy radiated went down.

The more mathematically inclined will probably see why straight away. Once you have relationships that aren’t linear the results doesn’t usually change in proportion to the inputs.

Well, energy radiated out is more important in climate than some “arithmetic average of temperature”.

When Trenberth and Kiehl updated their excellent 1997 paper in 2008 the average energy radiated up from the earth’s surface was changed from 390W/m2 to 396W/m2. The reason? You can’t average the temperature and then work out the energy radiated from that one average (how they did it in 1997). Instead you have to work out the energy radiated all around the world and then average those numbers (how they did it in 2008).

Conclusion

Measuring the temperature of air to work out the temperature of the ground is problematic and expensive to get right. And requires lot of knowledge about changing wind patterns at night.

And even if we measure it accurately, how useful is it?

Oceans store heat, the atmosphere is an irrelevance as far as heat storage is concerned. If the oceans cool, the atmosphere will follow. If the oceans heat up, the atmosphere will follow.

And why take a lot of measurements and take an arithmetic average? If we want to get something useful from the surface temperatures all around the globe we should convert temperatures into energy radiated.

And I hope to cover ocean heat content in a follow up post..

Update – check out The Real Measure of Global Warming

References

Detection of urban warming in recent temperature trends in Japan, Fumiaki Fujibe, International Journal of Climatology (2009)

Unresolved issues with the assessment of multidecadal global land surface temperature trends, Roger A. Pielke Sr. et al, Journal of Geophysical Research (2007)

Does a Global Temperature Exist? C. Essex et al, Journal of Nonequilibrium Thermodynamics (2007)

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New Theory Proves AGW Wrong!

Posted in Commentary on February 26, 2010| 38 Comments »

I did think about starting this post by pasting in some unrelated yet incomprehensible maths that only a valiant few would recognize, and finish with:

And so, the theory is overturned

But that might have put off many readers from making it past the equations, which would have been a shame, even though the idea was amusing.

From time to time new theories relating to, and yet opposing, the “greenhouse” effect or something called AGW, get published in a science journal somewhere and make a lot of people happy.

What is the theory of AGW?

If we are going to consider a theory, then at the very least we need to understand what the theory claims. It’s also a plus to understand how it’s constructed, what it relies on and what evidence exists to support the theory. We also should understand what evidence would falsify the theory.

AGW usually stands for anthropogenic global warming or the idea the humans, through burning of fossil fuels and other activities have added to the CO2 in the atmosphere, thereby increased the “greenhouse” effect and warmed the planet. And the theory includes that the temperature rise over the last 100 years or so is largely explained by this effect, and further increases in CO2 will definitely lead to further significant temperature rises.

So far on this blog I haven’t really mentioned AGW, until now. A few allusions here and there. One very minor non-specific claim at the end of Part Seven.

And yet there is a whole series on CO2 – An Insignificant Trace Gas? where the answer is “no, it’s not insignificant”.

Doesn’t that support AGW? Isn’t the theory of “greenhouse” gases the same thing as AGW?

The concept that some gases in the atmosphere absorb and then re-radiate longwave radiation is an essential component of AGW. It is one foundation. But you can accept the “greenhouse gas” theory without accepting AGW. For example, John Christy, Roy Spencer, Richard Lindzen, and many more.

Suppose during the next 12 months the climate science community all start paying close attention to the very interesting theory of Svensmart & Friis-Christensen who propose that magnetic flux changes from the sun induce cloud formation and thereby changing the climate in much more significant ways than greenhouse gases. Perhaps the climate scientists all got bored with their current work, or perhaps some new evidence or re-analysis of the data showed that it was too strong a theory to ignore. Other explanations for the same data just didn’t hold up.

By the end of that 12 months, suppose that a large part of the climate science community were nodding thoughtfully and saying “this explains all the things we couldn’t explain before and in fact fits the data better than the models which use greenhouse gases plus aerosols etc“.  (It’s a thought experiment..)

Well, the theory of AGW would be, if not dead, “on the ropes”. And yet, the theory that some gases in the atmosphere absorb and re-radiate longwave radiation would still be alive and well. The radiative transfer equations (RTE) as presented in the CO2 series would still hold up. And the explanations as to how much energy CO2 absorbed and re-radiated versus water vapor would not have changed a jot.

That’s because AGW is not “the greenhouse gas” theory. The “greenhouse gas” theory is an important and essential building block for AGW. It’s foundational atmospheric physics.

Many readers know this, of course, but some visitors may be confused over this point. Overturning the “greenhouse” theory would require a different approach. And in turn, that theory is based on a few elements each of which are very strong, but perhaps one could fall, or new phenomena could be found which affected the way these elements came together. It’s all possible.

So it is essential to understand what theory we are talking about. And to understand what that theory actually says, and what in turn, it depends on.

A Digression about the Oceans

Analogies prove nothing, they are illustrations. This analogy may be useful.

Working out the 3d path of the oceans around the planet is a complex task. You can read a little about some aspects of ocean currents in Predictability? With a Pinch of Salt please.. Computer models which attempt to calculate some aspects of the volume of warm water flowing northwards from the tropics to Northern Europe and then the cold water flowing southwards back down below struggle in some areas to get the simulated flow of water anywhere near close to the measured values (at least in the papers I was reading).

Why is that? The models use equations for conservation of momentum, conservation of angular momentum and density (from salinity and temperature). Plus a few other non-controversial theories.

Most people reading that there is a problem probably aren’t immediately thinking:

Oh, it’s got to be angular momentum, never believed in it!

Instead many readers might theorize about the challenges of getting the right starting conditions – temperature, salinity, flow at many points in the ocean. Then being able to apply the right wind-drag, how much melt-water flowing from Greenland, how cold that is.. And perhaps how well-defined the shape of the bottom of the oceans are in the models. How fine the “mesh” is..

We don’t expect momentum and density equations to be wrong. Of course, they are just theories, someone might publish a paper which picks a hole in conservation of momentum.. and angular momentum, well, never really believed in that!

The New Paper that Proves “The Theory” Wrong!

Let’s pick a theory. Let’s pick – solving the radiative transfer equations in a standard atmosphere. In laymans terms this would include absorption and re-radiation of longwave radiation by various trace gases and the effect on the temperature profile through the atmosphere – we could call it the “greenhouse theory”.

Ok.. so a physicist has a theory that he claims falsifies our theory. Has he proven our “greenhouse theory” wrong?

We establish that, yes, he is a physicist and has done some great work in a related or similar field. That’s a good start. We might ask next?

Has the physicist published the theory anywhere?

So what we are asking is, has anyone of standing checked the paper? Perhaps the physicist has a good idea but just made a mistake. Used the wrong equation somewhere, used a minus sign where a plus sign should have been, or just made a hash of re-arranging some important equation..

Great, we find out that a journal has published the paper.

So this proves the theory is right?

Not really. It just proves that the editor accepted it for publication. There might be a few reasons why:

  • the editor is also convinced that an important theory has been overturned by the new work and is equally excited by the possibilities
  • the editor thought that it was interesting new approach to a problem that should see the light of day, even though he thinks it’s unlikely to survive close scrutiny
  • the editor is fed up with being underpaid and overworked and there aren’t enough papers being submitted
  • the editor thinks it will really wind up Gavin Schmidt and this will get him to the front of the queue quicker

Well, people are people. All we know is one more person probably thinks it is a decent approach to a problem. Or was having an off day.

For a theory to become “an accepted theory” (because even the theory of gravity is “a theory” not “a fact”) it usually takes some time to be accepted by the people who understand that field.

Sheer Stubbornness and How to be Right

The fact that it’s not accepted by the community of scientists in that discipline doesn’t mean it’s wrong. People who have put their life’s work behind a theory are not going to be particularly accepting. They might die first!

How scientific theories get overturned is a fascinating subject. Those who don’t mind reading quite turgid work describing a fascinating subject might enjoy The Structure of Scientific Revolutions by Thomas Kuhn. No doubt there are more fun books that others can recommend.

The new theory might be right and it might be wrong. The fact that it’s been published somewhere is only the first step on a journey. If being published was sufficient then what to make of opposing papers that both get published?

Why Papers which Prove “it’s all wrong” are Celebrated

Many people are skeptical of the AGW theory.

Some are skeptical of “greenhouse gas” theory. Some accept that theory in essence but are skeptical of the amount that CO2 contributes to the “greenhouse” gas effect.

Some didn’t realize there was a difference..

If you are skeptical about something and someone with credentials agrees with you, it’s a breath of fresh air! Of course, it’s natural to celebrate.

But it’s also important to be clear.

If, for example, you celebrate Richard Lindzen’s concept as put forward in Lindzen & Choi (2009) then you probably shouldn’t be celebrating Miskolczi’s paper. And if you celebrated either of those, you shouldn’t be celebrating Gerlich & Tscheuschner because they will be at odds with the previous ones (as far as I can tell). And if you like Roy Spencer’s work, he is at odds this all of these.

Now, please don’t get me wrong, I don’t want to attack anyone’s work. Lindzen and Choi’s paper is very interesting although I had a lot of questions about it and maybe will get an opportunity at some stage to explain my thoughts. And of course, Professor Lindzen is a superstar physicist.

Miskolczi’s paper confused me and I put it aside to try and read it again – update April 2011, some major problems as explained in The Mystery of Tau – Miskolczi and the following two parts. And I thought it might be easier to understand the evidence that would falsify that theory (and then look for it) than lots of equations. Someone just pointed me to Gerlich & Tscheuschner so I’m not far into it. Perhaps it’s the holy grail – update, full of huge errors as explained in On the Miseducation of the Uninformed by Gerlich and Tscheuschner (2009).

And Lindzen and Choi’s is in a totally different category which is why I introduced it. Widely celebrated as proving the death of AGW beyond a shadow of doubt by the illustrious and always amusing debater Christopher Monckton, they aren’t at odds with “greenhouse gas” theory. They are at odds with the feedback resulting from an increase in “radiative forcing” from CO2 and other gases. They are measuring climate sensitivity. And as many know and understand, the feedback or sensitivity is the key issue.

So, if New Theory Proves AGW Wrong is an exciting subject, you will continue to enjoy the subject for many years, because I’m sure there will be many more papers from physicists “proving” the theory wrong.

However, it’s likely that if they are papers “falsifying” the foundational “greenhouse” gas effect – or radiative-convective model of the atmosphere – then probably each paper will also contradict the ones that came before and the ones that follow after.

Well, predictions are hard to make, especially about the future. Perhaps there will be a new series on this blog Why CO2 Really is Insignificant. Watch out for it.

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The Confirmation Bias – Or Why None of Us are Really Skeptics

Posted in Commentary on February 12, 2010| 7 Comments »

Perhaps I should say most of us are not really skeptics.

The Black Swan by Nassim Nicholas Taleb is such a well-written book. One of his subjects is the confirmation bias.

Consider a scientific theory. Most people coming to this blog are probably interested in science in some shape or form and know that for a theory to be scientific it has to be falsifiable – that is, we have to be able to create some tests in advance and say “if it fails these tests then the theory is not true”.

For example, the pink fairy down the bottom of my garden. I say it exists. You say, “Why can’t I see it?”

I say, “It’s invisible.” You ask, “How do I know it’s there?”

And so, in the end I have to provide some kind of evidence that can be tested. Otherwise it’s not a scientific theory.

Taleb gives a great example of what we all really do in practice, from research by pyschologists. Pay attention to Nicholas..

Subjects were presented with the three number sequence 2, 4, 6 and asked to guess the rule generating it. Their method of guessing was to produce other three-number sequences to which the experimenter would say “yes” or “no” depending on whether the new sequences were consistent with the rule.

What did the subjects do? They tried to guess the rule.. of course! That’s what they should have done.

And then they tested it by.. producing a sequence consistent with their theory. So almost no one worked out that the real rule was simply, “numbers in ascending order”

Perhaps they decided that the rule was a starting number x1, x2, x3. Or perhaps they decided that the rule was to take starting number then add 2, and add 2 again.

And they generated a sample sequence from their theory and told the experimenter.

But what almost no one did was to suggest a sequence inconsistent with their own mental theory – a test which would allow them to more easily falsify their theory.

The scientific method is to find a way to falsify a theory, but unconsciously almost all of us just try to corroborate our own theories.

Don’t look at the people around you.. ask yourself,

Do I try and test my theories by falsifying them?

Do I try and understand what my “opponents” say?

Do I spend time at blogs where I feel uncomfortable with their “false and unwarranted” conclusions of the world? And try and understand why they think what they do?

Become a real skeptic. Try and prove yourself wrong!

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The IPCC and the Credibility of Climate Science

Posted in Climate Models, Commentary on January 26, 2010| 4 Comments »

If you’re not a veteran of the blogosphere wars about climate change but have followed recent events you are probably wondering what to believe.

First, what recent events (Jan 2010)?

The issues arising from the story in the UK Mail that the IPCC used “sexed-up” climate forecasts to put political pressure on world leaders:

Dr Murari Lal also said he was well aware the statement (about Himalayan glaciers melting by 2035), in the 2007 report by the Intergovernmental Panel on Climate Change (IPCC), did not rest on peer-reviewed scientific research.

In an interview with The Mail on Sunday, Dr Lal, the co-ordinating lead author of the report’s chapter on Asia, said: ‘It related to several countries in this region and their water sources. We thought that if we can highlight it, it will impact policy-makers and politicians and encourage them to take some concrete action.

Then there are a number of stories on a similar theme where the predictions of climate change catastrophe weren’t based on “peer-reviewed” literature but on reports from activist organizations, like the WWF. And the reports were written not by specialists in the field, but activists..

And these follow the “climategate” leak of November 2009 where emails from the CRU from prominent IPCC scientists like Phil Jones, Michael Mann, Keith Briffa and others show them in a poor light.

This blog is focused on the science but once you read stories like this you wonder how much of anything to believe.

  • For some, the science is settled, these are distractions by the right/big oil/energy companies and what is there to discuss?
  • For others, we knew all along that the IPCC is a green/marxist plot to take over world government, what is there to discuss?

If you are in one of those mindsets, this blog is probably the wrong place to come.

Be Skeptical

Being skeptical doesn’t mean not believing anything you hear. Being skeptical means asking for some evidence.

I see many individuals watching the recent events unfolding and saying:

See! CO2 can’t cause climate change. It’s all a scam.

Actually the two aren’t related. CO2 and the IPCC are not an indivisible unit!

It’s a challenge to keep a level head. To be a good skeptic means to realize that an organization can be flawed, corrupt even, but it doesn’t mean that all the people whose work it has drawn on have produced junk science.

When a government tries to convince its electorate that it has produced amazing economic results by stretching or inventing a few statistics, does this mean the statisticians working for that government are all corrupt, or even that the very science of statistics is clearly in error?

Most people wouldn’t come to that conclusion.

Politics and Science

But in climate science it’s that much harder because to understand the science itself takes some effort. The IPCC is a political body formed to get political momentum behind action to “prevent climate change”. Whereas climate science is mostly about physics and chemistry.

They are a long way apart.

For myself, I believe that the IPCC has been bringing the science of climate into disrepute for a long time, despite producing some excellent work.  It has claimed too much certainty about what the science can predict. Tenuous findings that might possibly show that a warmer world will lead to more problems are pressed into service. Findings against are ignored.

This causes a problem for anyone trying to find out the truth.

It’s tempting to dismiss anything that is in an IPCC report because of these obvious flaws – and they have been obvious for a long time. But even that would be a mistake. Much of what the IPCC produces is of a very high quality. They have a bias, so don’t take it all on faith..

The Easy Answer

Find a group of people you like and just believe them.

The Road Less Travelled

My own suggestion, for what it’s worth, is to put time into trying to get a better understanding of climate science. Then it is that much easier to separate fact from fiction. One idea – if you live near a university, you can visit their library and probably find a decent entry-level book or two about climate science basics.

Another idea – for around $40 you can purchase Elementary Climate Physics by Prof. F.W. Taylor – from http://www.bookdepository.co.uk/ – free shipping around the world. Amazing. And I don’t get paid for this advert either, not until I work out how to get adverts down the side of the blog. It’s an excellent book with some maths, but skip the maths and you will still learn 10x more than reading any blog including mine.

And, of course, visit blogs which focus on the science and ask a few questions.

Be prepared to change your mind.

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“Warmest Decade on Record” and the Layman’s Guide to Autocorrelation

Posted in Commentary, Measurement on January 4, 2010| 4 Comments »

In many debates on whether the earth has been cooling this decade we often hear

This decade is the warmest on record

(Note: reference is to the “naughties” decade).

This post isn’t about whether or not the temperature has gone up or down but just to draw attention to a subject that you would expect climate scientists and their marketing departments to handle better.

An Economic Analogy

Analogies don’t prove anything, but they can be useful illustrations, especially for those whose heads start to spin as soon as statistics are mentioned.

Suppose that the nineties were a roaring decade of economic progress, as measured by the GDP of industrialized nations (and ignoring all problems relating to what that all means). And suppose that the last half century with a few ups and downs had been one of strong economic progress.

Now suppose that around the start of the new millennium the industrialized nations fell into a mild recession and it dragged on for the best part of the decade. Towards the end of the decade a debate starts up amongst politicians about whether we are in recession or not.

There would be various statistics put forward, and of these the politicians out of power would favor the indicators that showed how bad things were. The politicians in power would favor the indicators that showed how good things were, or at least “the first signs of economic spring”.

Suppose in this debate some serious economists stood up and said,

But listen everyone, this decade has the highest GDP of any decade since records began.

What would we all think of these economists?

The progress that had taken the world to the start of the millennium would be the reason for the high GDP in the “naughties” decade. It doesn’t mean there isn’t a recession. In fact, it tells you almost nothing about the last few years. Why would these economists be bringing it up unless they didn’t understand “Economics 101”?

GDP and other measures of economic prosperity have a property that they share with the world’s temperature. The status at the end of this year depends in large part on the status at the end of last year.

In economics we can all see how this works. Prosperity is stored up year after year within the economic system. Even if some are spending like crazy others are making money as a result. When hard times come we don’t suddenly reappear, in economic terms, in 1935.

In climate it’s because the earth’s climate system stores energy. This is primarily the oceans and cryosphere (ice) but also includes the atmosphere.

Auto-Correlation for the total layman/woman who doesn’t want to hear about statistics

For those not statistically inclined, don’t worry this isn’t a technical treatment.

When various people analyze the temperature series for the last few decades they usually try and work out some kind of trend line and also other kinds of statistical treatments like “standard deviation”.

You can find lots of these on the web. I’m probably in a small minority but I don’t see the point of most of them. More on this at Is the climate more than weather? Is weather just noise?

However, for those who do see the point and carry out these analyses to prove or disprove that the world is warming or cooling in a “statistically significant” way, the more statistically inclined will be sure to mention one point. Because the temperature from year to year is related strongly to the immediate past – or in technical language “auto-correlated” – this changes the maths and widens the error bars.

Auto-correlation in layman’s terms is what I described in the economic analogy. Next year depends in large part on what happened last year.

Why mention this?

First, a slightly longer explanation of auto-correlation – skip that section if you are not interested..

Auto-Correlation in a little more detail

If you ever read anything about statistics you would have read about “the coin toss”.

I toss a coin – it’s 50/50 whether it comes up heads or tails. I have one here, flipping.. catching.. ok, trust me it’s heads.

Now I’m going to toss the coin again. What are the odds of heads or tails? Still 50/50. Ok, tossing.. heads again.

Now I’m going to toss the coin a 3rd time. At this point you check the coin and get it scientifically analyzed. Finally, much poorer, you hand me back the coin because it’s been independently verified as a “normal coin”. Ok so I toss the coin a 3rd time and it’s still 50/50 whether it lands heads or tails.

Many people who have never been introduced to statistics – like all the people who play roulette for real money that matters to them – have no concept of independent statistical events.

It’s a simple concept. What happened previously to the coin when I flipped it has absolutely no effect on a future toss of the coin. The coin has no memory. The law of averages doesn’t change the future. If I have tossed 10 heads in a row the next toss of this standard coin is no more likely to be tails than heads.

In statistics, the first kind of problems that are covered are ones where each event or each measurement are “independent”. Like the coin toss. This makes analysis of calculation of the mean (average) and standard deviation (how spread out the results are) quite simple.

Once a measurement or event is dependent in some way on the last reading (or an earlier reading) it gets much more complicated.

In technical language: Autocorrelation is the correlation of a signal with itself

If you want to assess a series of temperature measurements and work out a trend line and statistical significance of the results you need to take account of its auto-correlation.

What’s the Point?

What motivated this post was watching the behavior of some climate scientists, or at least their marketing departments. You can see them jump into many debates to point out that the error bars aren’t big enough on a particular graph, with a sad shake of their head as if to say “why aren’t people better at stats? why do we have to keep explaining the basics? you have to use an ARMA(1,1) process..”

But the same people, in debates about current cooling or warming, keep repeating

This decade IS the warmest decade on record

as if they hadn’t heard the first thing about auto-correlation.

Statistically minded climate scientists, like our mythical economists earlier, should be the last people to make that statement. And they should be the first to be coughing slightly and putting up a hand when others make that point in the context of whether the current decade is warming or cooling.

Conclusion

Figuring out whether the current decade is cooling or warming isn’t as easy as it might seem and isn’t the subject of this post.

But next time someone tells you “This decade IS the warmest decade on record” – which means in the last 150 years, or a drop in the geological ocean – remember that it is true, but doesn’t actually answer the question of whether the last 10 years have seen warming or cooling.

And if they are someone who appears to know statistics, you have to wonder. Are they trying to fool you?

After all, if they know what auto-correlation is there’s no excuse.

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Understanding the Flaw

Posted in Climate Models, Commentary on December 13, 2009| 38 Comments »

The debate about climate change is a very polarized one.

Understanding the points of view of people who disagree with you is essential to making progress. Even more importantly, you should understand the arguments that summarize the best of the opposite point of view.

Much that is written in the general media is the “polarized view”. So here is a wonderful open letter from a climate scientist that sums up a “skeptical” point of view in a humble way. Emphasis added.

I would add that the view presented is also the point of view of this blog. Standing on the shoulders of giants..

=====================

Date: Mon, 07 Dec 2009 08:28:38 -0700
From: Petr Chylek
To: Climate@lanl.gov, energy@lanl.gov, isr-all@lanl.gov, ees-all@lanl.gov

Dear Climate People:

FYI below is a letter that I sent on Saturday to about 100 top climate research experts including Jim Hansen, Steve Schneider, Phil Jones (UK) and other superstars. Till now I got 14 replies which are about 50/50 between supporting of what I said and defense of the IPCC process.

Greetings,
Petr

=====================

Open Letter to the Climate Research Community

I am sure that most of you are aware of the incident that took place recently at the University of East Anglia’s Climatic Research Unit (CRU). The identity of the whistle-blower or hacker is still not known.

The selected release of emails contains correspondence between CRU scientists and scientists at other climate research institutions. My own purely technical exchange of emails with CRU director Professor Phil Jones is, as far as I know, not included.

I published my first climate-related paper in 1974 (Chylek and Coakley, Aerosol and Climate, Science 183, 75-77). I was privileged to supervise Ph. D. theses of some exceptional scientists – people like J. Kiehl, V. Ramaswamy and J. Li among others. I have published well over 100 peer-reviewed papers, and I am a Fellow of the American Geophysical Union, the Optical Society of America, and Los Alamos National Laboratory. Within the last few years I was also honored to be included in Wikipedia’s blacklist of “climate skeptics”.

For me, science is the search for truth, the never-ending path towards finding out how things are arranged in this world so that they can work as they do. That search is never finished.

It seems that the climate research community has betrayed that mighty goal in science. They have substituted the search for truth with an attempt at proving one point of view. It seems that some of the most prominent leaders of the climate research community, like prophets of Old Israel, believed that they could see the future of humankind and that the only remaining task was to convince or force all others to accept and follow. They have almost succeeded in that effort.

Yes, there have been cases of misbehavior and direct fraud committed by scientists in other fields: physics, medicine, and biology to name a few. However, it was misbehavior of individuals, not of a considerable part of the scientific community.

Climate research made significant advancements during the last few decades, thanks to your diligent work. This includes the construction of the HadCRUT and NASA GISS datasets documenting the rise of globally averaged temperature during the last century. I do not believe that this work can be affected in any way by the recent email revelations. Thus, the first of the three pillars supporting the hypothesis of manmade global warming seems to be solid.

However, the two other pillars are much more controversial. To blame the current warming on humans, there was a perceived need to “prove” that the current global average temperature is higher than it was at any other time in recent history (the last few thousand years). This task is one of the main topics of the released CRU emails. Some people were so eager to prove this point that it became more important than scientific integrity.

The next step was to show that this “unprecedented high current temperature” has to be a result of the increasing atmospheric concentration of carbon dioxide from the burning of fossil fuels. The fact that the Atmosphere Ocean General Circulation Models are not able to explain the post-1970 temperature increase by natural forcing was interpreted as proof that it was caused by humans. It is more logical to admit that the models are not yet good enough to capture natural climate variability (how much or how little do we understand aerosol and clouds, and ocean circulation?), even though we can all agree that part of the observed post-1970 warming is due to the increase of atmospheric CO2 concentration. Thus, two of the three pillars of the global warming and carbon dioxide paradigm are open to reinvestigation.

The damage has been done. The public trust in climate science has been eroded. At least a part of the IPCC 2007 report has been put in question. We cannot blame it on a few irresponsible individuals. The entire esteemed climate research community has to take responsibility. Yes, there always will be a few deniers and obstructionists.

So what comes next? Let us stop making unjustified claims and exaggerated projections about the future even if the editors of some eminent journals are just waiting to publish them. Let us admit that our understanding of the climate is less perfect than we have tried to make the public believe. Let us drastically modify or temporarily discontinue the IPCC. Let us get back to work.

Let us encourage students to think their own thoughts instead of forcing them to parrot the IPCC conclusions. Let us open the doors of universities, of NCAR, NASA and other research institutions (and funding agencies) to faculty members and researchers who might disagree with the current paradigm of carbon dioxide. Only open discussion and intense searching of all possibilities will let us regain the public’s trust and move forward.

Regards,
Petr Chylek

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